<template>
  <div>
       <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
        <el-breadcrumb-item :to="{ path: '/' }">首页</el-breadcrumb-item>
        <el-breadcrumb-item>商品管理</el-breadcrumb-item>
        <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区 -->
    <el-card>
        <!-- 警告区域 -->
        <el-alert
            title="注意：只允许为第三级分类设置相关参数"
            type="warning" :closeable='false' show-icon>
        </el-alert>
        <!-- 选择商品分类区域 -->
        <el-row class="cat_opt">
            <el-col>
                <span>选择商品分类：</span>
                <!-- 选择商品分类的级联选择框 -->
                <el-cascader
                    v-model="selectedCateKeys"
                    :options="catelist"
                    expandTrigger= 'hover'
                    :props="cateProps" @change="handleChange"></el-cascader>
            </el-col>
        </el-row>
        <!-- tab页签区域 -->
        <el-tabs v-model="activeName" @tab-click="handleTabClick">
            <!-- 添加动态参数的面板 -->
            <el-tab-pane label="动态参数" name="many">
                <!-- 添加参数按钮 -->
            <el-button type='primary' size='mini' :disabled='isBtnDisable' @click="addDialogVisible = true">添加参数</el-button>
            <!-- 动态参数表格 -->
            <el-table :data='manyTableData' border stripe>
                <!-- 展开行 -->
                <el-table-column type='expand'>
                    <template slot-scope="scope">
                        <!-- 循环渲染tag标签 -->
                        <el-tag v-for="(item,i) in scope.row.attr_vals" :key='i' closable @close='handleClose(i,scope.row)'>{{item}}</el-tag>
                        <!-- 输入文本框 -->
                        <el-input
                        class="input-new-tag"
                        v-if="scope.row.inputVisible"
                        v-model="scope.row.inputValue"
                        ref="saveTagInput"
                        size="small"
                        @keyup.enter.native="handleInputConfirm(scope.row)"
                        @blur="handleInputConfirm(scope.row)"
                        >
                        </el-input>
                        <!-- 添加按钮 -->
                        <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                    </template>
                </el-table-column>
                <!-- 索引列 -->
                <el-table-column type='index'></el-table-column>
                <el-table-column label='参数名称' prop='attr_name'></el-table-column>
                <el-table-column label='操作'>
                    <template slot-scope="scope">
                    <el-button type='primary' icon='el-icon-edit' size='mini' @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                    <el-button size='mini' type='danger' icon='el-icon-delete' @click="removeParams(scope.row.attr_id)">删除</el-button>
                    </template>
                </el-table-column>
            </el-table>
            </el-tab-pane>
            <!-- 添加静态参数的面板 -->
            <el-tab-pane label="静态属性" name="only">
                <!-- 添加属性按钮 -->
                <el-button type='primary' size='mini' :disabled='isBtnDisable' @click="addDialogVisible = true">添加属性</el-button>
                <!-- 静态参数表格 -->
                <el-table :data='onlyTableData' border stripe>
                    <!-- 展开行 -->
                   <el-table-column type='expand'>
                    <template slot-scope="scope">
                        <!-- 循环渲染tag标签 -->
                        <el-tag v-for="(item,i) in scope.row.attr_vals" :key='i' closable @close='handleClose(i,scope.row)'>{{item}}</el-tag>
                        <!-- 输入文本框 -->
                        <el-input
                        class="input-new-tag"
                        v-if="scope.row.inputVisible"
                        v-model="scope.row.inputValue"
                        ref="saveTagInput"
                        size="small"
                        @keyup.enter.native="handleInputConfirm(scope.row)"
                        @blur="handleInputConfirm(scope.row)"
                        >
                        </el-input>
                        <!-- 添加按钮 -->
                        <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                    </template>
                </el-table-column>
                    <!-- 索引列 -->
                    <el-table-column type='index'></el-table-column>
                    <el-table-column label='属性名称' prop='attr_name'></el-table-column>
                    <el-table-column label='操作'>
                        <template slot-scope="scope">
                        <el-button type='primary' icon='el-icon-edit' size='mini' @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                        <el-button size='mini' type='danger' icon='el-icon-delete' @click="removeParams(scope.row.attr_id)">删除</el-button>
                        </template>
                    </el-table-column>
                </el-table>
            </el-tab-pane>
        </el-tabs>
    </el-card>
    <!-- 添加参数的对话框 -->
    <el-dialog
    :title="'添加'+ titleText"
    :visible.sync="addDialogVisible"
    width="50%" @close='addDialogClosed'>
        <!-- 添加参数的对话框 -->
        <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
            <el-form-item :label="titleText" prop="attr_name">
                <el-input v-model="addForm.attr_name"></el-input>
            </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
            <el-button @click="addDialogVisible = false">取 消</el-button>
            <el-button type="primary" @click="addParams">确 定</el-button>
        </span>
    </el-dialog>
    <!-- 修改参数对话框 -->
    <el-dialog
    :title="'修改'+ titleText"
    :visible.sync="editDialogVisible"
    width="50%" @close='editDialogClosed'>
    <!-- 修改参数的对话框 -->
    <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
            <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
    </el-form>
    <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
    </span>
</el-dialog>
  </div>
</template>

<script>
export default {
    data(){
        return{
            // 商品分类列表
            catelist:[],
            // 级联选择框的配置对象
            cateProps:{
                value:'cat_id',
                label:'cat_name',
                children:'children'
            },
            // 级联选择框双向绑定到的数组
            selectedCateKeys:[],
            // 被激活的页签名称
            activeName:'many',
            // 动态参数数据
            manyTableData:[],
            // 静态属性的数据
            onlyTableData:[],
            // 控制添加对话框的显示与隐藏
            addDialogVisible:false,
            // 添加数据的表单数据对象
            addForm:{},
            // 添加参表单的验证规则对象
            addFormRules:{
                attr_name:[
                    {required:true,message:'请输入参数名称',trigger:'blur'}
                ]
            },
            // 控制修改对话框的显示与隐藏
            editDialogVisible:false,
            // 修改的表单数据对象
            editForm:{},
            // 修改表单的验证规则对象
            editFormRules:{
                attr_name:[
                    {required:true,message:'请输入参数名称',trigger:'blur'}
                ]
            },
            // 控制按钮与文本框的切换显示
            inputVisible:false,
            // 文本框中输入的内容
            inputValue:''
        }
    },
    created(){
        this.getCateList()
    },
    methods:{
        // 获取所有的商品分类列表
        async getCateList(){
            const {data:res} = await this.$http.get('categories')
            if(res.meta.status !==200){
                return this.$message.error('获取商品分类失败！')
            }
            this.catelist = res.data
        },
        // 级联选择框选中项变化，会触发这个函数
        async handleChange(){
           this.getParamsData()
        },
        // 获取参数的列表数据
        async getParamsData(){
            // 证明选中的不是三级分类
            if(this.selectedCateKeys.length !==3 ){
                this.selectedCateKeys = []
                this.manyTableData = []
                this.onlyTableData = []
                return
            }
            // 证明选中的是三级分类
            // 根据所选分类的id和当前所处的面板，获取对应的参数
            const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`,{params:{sel:this.activeName}})
            if(res.meta.status !==200){
                return this.$message.error('获取参数列表失败！')
            }
            res.data.forEach(item => {
                item.attr_vals = item.attr_vals ?item.attr_vals.split(' ') : []
                // 控制文本框的显示与隐藏
                item.inputVisible = false
                //文本框中输入的值
                item.inputValue = ''
            })
            if(this.activeName === 'many'){
                this.manyTableData = res.data
            }else{
                this.onlyTableData = res.data
            }
        },
        // 这是tab页签点击事件的处理函数
        handleTabClick(){
            this.getParamsData()
        },
        // 监听对话框的关闭事件
        addDialogClosed(){
            this.$refs.addFormRef.resetFields()
        },
        // 点击按钮添加餐
        addParams(){
            this.$refs.addFormRef.validate(async valid =>{
                if(!valid) return
                const {data:res} = await this.$http.post(`categories/${this.cateId}/attributes`,{attr_name:this.addForm.attr_name,attr_sel:this.activeName})
                if(res.meta.status !==201){
                    return this.$message.error('添加参数失败！')
                }
                this.$message.success('添加参数成功！')
                this.addDialogVisible = false
                this.getParamsData()
            })
             
        },
        // 点击按钮，展示修改参数对话框
        async showEditDialog(attr_id){
            // 查询当前参数的信息
            const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`,{parmars:{attr_sel:this.activeName}})
            if(res.meta.status !==200){
                return this.$message.error('获取参数信息失败！')
            }
            this.editForm = res.data
            this.editDialogVisible = true
        },
        // 重置修改的表单
        editDialogClosed(){
            this.$refs.editFormRef.resetFields()
        },
        //点击按钮，修改参数信息
        editParams(){
            this.$refs.editFormRef.validate(async valid =>{
                if(!valid) return
                const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{attr_name:this.editForm.attr_name,attr_sel:this.activeName})
                if(res.meta.status !==200){
                    return this.$message.error('修改参数失败！')
                }
                this.$message.success('修改参数成功！')
                this.editDialogVisible = false
                this.getParamsData()
            })
        },
        // 根据id删除对应的参数项
        async removeParams(attr_id){
            const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
            confirmButtonText: '确定',
            cancelButtonText: '取消',
            type: 'warning'
            }).catch(err=>err)
            // 用户取消了删除操作
            if(confirmResult !== 'confirm'){
                return this.$message.info('已取消删除！')
            }
            // 删除的业务逻辑
            const {data:res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)
            if(res.meta.status !==200){
                return this.$message.error('删除参数失败！')
            }
            this.$message.success('删除参数成功！')
            this.getParamsData()
        },
        // 文本框失去焦点，或摁下了enter都会触发
        async handleInputConfirm(row){
            if(row.inputValue.trim().length === 0){
                row.inputValue = ''
                row.inputVisible = false
                return
            }
            // 如果没有return，则证明输入的内容需要做后续处理
            row.attr_vals.push(row.inputValue.trim())
            row.inputValue = ''
            row.inputVisible = false
            this.saveAttrVals(row)
        },
        // 将对attr_vals的操作，保存到数据库
        async saveAttrVals(row){
            // 需要发起请求保存操作
            const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
                attr_name:row.attr_name,
                attr_sel:row.attr_sel,
                attr_vals:row.attr_vals.join(' ')
            })
            if(res.meta.status !==200){
                return this.$message.error('修改参数项失败！')
            }
            this.$message.success('修改参数项成功！')
        },
        // 点击按钮，展示文本输入框
        showInput(row){
            row.inputVisible = true
            // 让文本框自动获得焦点
            // $nextTick方法的作用，当页面上元素被重新渲染之后，才会指定回调函数中的代码
            this.$nextTick(_ => {
                this.$refs.saveTagInput.$refs.input.focus();
            });
        },
        // 删除对应的可选项
        handleClose(i,row){
            row.attr_vals.splice(i,1)
            this.saveAttrVals(row)
        }
    },
    computed:{
        // 如果按钮需要被禁用，则返回true，否则返回false
        isBtnDisable(){
            if(this.selectedCateKeys.length !==3 ){
                return true
            }
            return false
        },
        // 当前选中的三级分类的id
        cateId(){
            if(this.selectedCateKeys.length === 3){
                return this.selectedCateKeys[2]
            }
            return null
        },
        // 动态计算标题的文本
        titleText(){
            if(this.activeName === 'many'){
                return '动态参数'
            }
            return '静态属性'
        }
    }
}
</script>

<style lang='less' scoped>
.cat_opt{
    margin: 15px 0;
}
.el-tag{
    margin: 10px;
}
.input-new-tag{
    width:120px
}
</style>